PM%20Concluding%20Workshop

1
Roadside Measurements of Particulate Matter (PM)
size distribution
P.J. Sturm, S. Hausberger
Graz University of Technology Michael Bacher,
Bernhard Lechner, Bernhard Heiden Paul Scherrer
Institute Urs Baltensperger, David Imhof, Ernest
Weingartner, Andre S.H. PrevotBergische
Universität Wuppertal Ralf Kurtenbach, Peter
Wiesen TRL Ian McCrae, Paul Boulter
2
Measurement Programme

• Roadside measurements were performed with the
  intention to document the size distribution of PM
  under dilution conditions similar to those found
  in real world
• Measurements at
• engine test beds
• at different locations in a road tunnel
• at different locations in urban environment

3
Engine measurements
Euro 3, HDVSampling according to Particulates
procedure
4
City Bus
5
Tunnel measurements
6
Tunnel measurements
Ambient air (site 1)
Kerb side (site 2)
Ventilation shaft (site 3)
Ventilation outlet (site 4)
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Tunnel measurements kerb side
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Tunnel measurements ventilation outlet
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Tunnel measurements Principal Component Analyses
(PCA)
The PCA tries to explain data as a combination of
influencing factors, i.e. the principal
components (PC), and weighing factors (t), which
describe the individual weight of each of these
PCs.
PC1 looks like median of data With PC1 and PC 2
80 of all data can be described
10
Tunnel measurements first PC
11
Tunnel measurements second PC
12
Tunnel measurements factors for site 4
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Urban air measurements kerb side
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Urban air measurements urban background
15
Conclusions

• The engine measurements show a size distribution
  strongly dependent on engine load
• At higher loads main peak in the 80 - 100 nm
  range
• The kerb-side measurements in the tunnel show an
  aerosol size distribution strongly varying with
  the traffic volume
• Depending on the traffic and ventilation
  situation nucleation mode particles or soot mode
  particles dominate. Main peak in the 80 100 nm
  range

16
Conclusions - 2

• The kerb side measurements at an intersection
  show a distribution having a peak at 25 nm ,
  along with smaller nucleation particles around 10
  nm
• The pure soot mode (80 nm range) which is present
  in the engine and the tunnel measurements is
  hardly visible in this case
• Measurements in the urban background show that
  almost no nucleation mode particles are present
  in the urban background
• The mode of the size distribution is slightly
  shifted towards larger particles, the maximum is
  the 25 to 35 nm range

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Conclusions - 3

• Tunnel measurements offer the possibility of
  investigating emissions from a huge variety of
  road vehicles. They are thus an optimal means for
  investigating real world emission behaviour
• Contrary to gaseous pollutants, the PM size
  concentration due to emissions is influenced by
  the size distribution that is already present in
  the tunnel.
• Particle number size distribution profiles
  recorded in street tunnels do not necessarily
  represent situations occurring in ambient air